// Muduo - A reactor-based C++ network library for Linux
// Copyright (c) 2010, Shuo Chen.  All rights reserved.
// http://code.google.com/p/muduo/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
//   * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//   * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//   * Neither the name of Shuo Chen nor the names of other contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


#include <clusnet/base/Exception.h>
#include <stdlib.h>
#include <execinfo.h>
#include <cxxabi.h>

using namespace clusnet::base;

Exception::Exception(const char* msg, bool demangle)
    : message_(msg)
{
    fillStackTrace(demangle);
}

Exception::Exception(const std::string& msg, bool demangle)
    : message_(msg)
{
    fillStackTrace(demangle);
}

Exception::~Exception() throw()
{
}

const char* Exception::what() const throw()
{
    return message_.c_str();
}

const char* Exception::stackTrace() const throw()
{
    return stack_.c_str();
}

void Exception::fillStackTrace(bool demangle)
{
    const int max_frames = 200;
    void* buffer[max_frames];
    int nptrs = ::backtrace(buffer, max_frames);
    char** stacks = ::backtrace_symbols(buffer, nptrs);
    if (stacks)
    {
        size_t funcnameSize = 256;
        char* funcname = demangle ? static_cast<char*>(::malloc(funcnameSize)) : nullptr;
        for (int i = 0; i < nptrs; ++i)
        {
            if (demangle)
            {
                char *begin_name = nullptr;
                char *name_offset = nullptr;

                for (char* p = stacks[i]; *p; ++p)
                {
                    if (*p == '(')
                    {
                        begin_name = p;
                    }
                    else if (*p == '+')
                    {
                        name_offset = p;
                        break;
                    }
                }
                if (begin_name && name_offset)
                {
                    *name_offset = '\0';
                    int status = 0;
                    char* ret = abi::__cxa_demangle(begin_name + 1, funcname, &funcnameSize, &status);
                    *name_offset = '+';
                    std::string result;
                    if (status == 0 && ret != nullptr)
                    {
                        // ret possibly realloc
                        funcname = ret;
                        stack_.append(stacks[i], begin_name + 1);
                        stack_.append(funcname);
                        stack_.append(name_offset);
                        stack_.push_back('\n');
                        continue;
                    }
                }
            }
            stack_.append(stacks[i]); 
            stack_.push_back('\n');
        }
        free(funcname);
        free(stacks);
    }
}
